Means for gravure printing of typographical characters



Dec. 15, 1953 H. R. FREUND MEANS FOR GRAVURE PRINT Original Filed June8, 1949 4:0 FIG. 4.

INVENTOR HERMAN R". FREUND BY $445,, M441 5% ATTORNEYS H. R. FREUND Dec.15, 1953 2 Sheets-$heet 2 Original Filed June 8, 1949 FIG. 7.

FIG. 6.

lNV ENTOR HERMAN R. FIPEU/VD BYE n ATTORNEY-5 Patented Dec. 15, 1953 mmST T S P T T MEANS FOR GRAVURE PRINTING OF TYPOGRAPHICAL CHARACTERSHermon RJFreund, Brooklyn, N. Y., assignor to p v Intertype Corporation,Brooklyn, N Y., a cotporzttionof New York Original application June 8,1949, Serial No. 91,882. Divided and this application Novemperfi, 1951,Serial No. 255,059 t V t iClaims. (Cl.95-4.5)

This invention relatesto gravure printing and a portion of a composedpage of type matter, in more particularly to typographicalcharacters andthe form, of at positive transparency, prepared characterbearing"ei'mentsfor iis i'n'the photoin accordance with the invention; 7graphic m 1 4 Figure 7 is aplanyiewpfe portion of aprintep .f i

practice of the intention; r V H The gra vlire printing process to whichthe means of the invention are directed is anintaglio the form of a webwhich islfed reletive s6v the rotating cylinder, The cylinder floodedwith inkend the surplus inkis then wiped off the nonfi his no vel efiectis acihg oriotherw setm l c c .7 m te cha ters (the l dthef i w he dpressed-printing areas t o the l ontline;ofueeoh movement of-thecylinderipastthef doctcr, it: is

:nsed; in tg'ravure .4 1 40 Punting 15 idl kfillllnbyithe paper: and,Figure' '2 'sh'ow'sthe printed impression made dries partiailyhyevaporati on,;due to its extreme dbyconventionai paper. 'The fromthepiinuri e mFi i lim 1 at l y, and Partially adsorption. into .t Figural?illu'stratewelimewhetireducedScale, rthe'fir'st of sexiera l stepsinoneoj then ethodsof The ink when applied to the paper spreadspreparing the printing surface, according to the slightly from the precseshape ofthe-individuai preseii'tlinventionf Y 1 c e t F fifiigu're' iillustrates a subsequent step in the screenpettern ofthe ridges inthe-printing surprocess within the scope of the inventioni I Heretofore,gravlire printing wsurfaces have "Figure 5 is a plan'vi'ew, zit enlargedstleQof a been customarily prepared fon reproducingtypematriiembodyingth present inyention prematter or text b ,nrsmom osmgithetextin pared; in accordance with the jp ocesses 0f Fiesolid-face type,and tgkinguajproof thereof on ores-Bend 4;' if p at of paper. Thisproof-Jis them -photo- 6 showeet the scale of Figures 1 and 2, graphed}and arm ive r n a a photograph having opaque letters on a transparentbackground-is formed from it. This is placed over a carbon tissue-asheet of gelatin sensitized to light, by means of potassium bichromatefor example, so that the normally water-soluble gelatin will be hardenedand rendered insoluble by the action of light. The carbon tissueis thenexposed to light through the positive transparency so that the gelatinis hardened everywhere except beneath the opaque letters of thetransparency. To produce the re-' posed portions of the gelatin. Thecylinder then is etched, for example with ferric chloride, through thecarbon tissue which serves as a resist and allows etching of thecylinder only where the gelatin has been washed away. The

strokes defining the configuration of the respective typographicalcharacters are thus etched as a network of tiny cells or depressions,with a criss-cross pattern of upstanding ridges separating and isolatingthe respective cells. This formation is illustrated in Figure 1 whereinthe ridges 22 which extend completely across the strokes of thecharacter divide the strokes into the sharp, square-cornered cells 28.

The printed impression made by such an the unhardened areascorrespondetched printing surface is shown in Figure 2.

The ink from each of the tiny ink retaining cells has spread on thepaper so that the screen pattern is obscured within the outline of theprinted character. However, due to the separations between the ink cells20 along the edges of the etched characters on the cylinder-the breaksproduced in the outline of the characters by the ridges 22-thereproduced characters have the serrated or jagged outline indicated inFigure 2, a defect which up to the present has characterized all typematter printed by the gravure process.

There have been various attempts heretofore to remedy the defectdescribed, but none of them has provided a practical solution. Forexample, it was suggested in Patent No. 843,947 to J. W. lppers that thejagged outlines of large, solidly colored decorative design areas inintaglio printing upon textile material could be eliminated byterminating the ridges of the screen pattern short of the outline of thedesign to form an ink retaining dam or channel around the boundary ofthe design area. However, the method proposed to form such channel andthe environment in which it was intended for use suggests no practicalapplication in the art of producing readable type matter, which requiresa degree of sharpness neither sought nor attainable in the textile art.The later Patent No. 2,456,608 to Harley C. Alger sought to apply theIppers principle to gravure printing of type matter. This patenthowever, discloses an unworkable process which depends upon manuallyengraving the screen pattern in the printing face of metal type members.These were supposed to be used in composing and printing a page of typematter to be photographed and used in etching the printing cylinder asabove described. The patent is not clear whether or not the type memberswere to be of enlarged size. If not, the invention would be altogetherimpractical because with a metal type member of the same size as thedesired ultimate printed reproduction, it would be impossible to engravein its face, by hand or by any available mechanical means, the extremelyfine screen patterns required in gravure work-often involving as many as22,500 minute, perfectly square and sharp-cornered depressions persquare inch of printing surface. Moreover, even if it were possible tomake such metal type members, they would be perpetually susceptible towear and damage to the extremely fine interstices of the engraving, andthe extremenly tiny ink cells would easily clog with ink and fineforeign particles from the atmosphere and from printing surfacescontacted by the type members.

If, on the other hand, it Was Algers intention that the metal typemembers be of a fairly enlarged size, the invention is impracticalbecause of the obviously intolerable awkwardness of handling such typemembers. There is no available machine by which such large and heavytype could be mechanically composed, so that extremely slow and costlyhand composition would be necessary. Even after the Alger patent,accordingly, the art has had no commercially practicable means forproducing type characters of sharp outline by the gravure printingprocess.

The use of the gravure process for the printed reproduction of typematter has accordingly been avoided insofar as possible, although, forthe printing of pictorial matter, gravure has many well recognizedadvantages over other processes. However, because of the manifestineconomy of printin the type matter of a publication by a differentprocess than that by which the pictorial matter of the same publicationis printed, the art has heretofore had either to forego the advantagesof gravure for pictorial work, or tolerate the inferior quality of typematter printed by gravure.

The present invention affords for the first time practical methods andmeans for producing type matter of good quality by gravure. The processof the invention commences with the preparation by drawing (which termis used herein to comprehend drawing, painting and other forms of manualpreparation such as composite mock-up) of a master typographicalcharacter such as is shown in Figures 3 and 4. One method of preparingsuch a character is illustrated in Figure 3 and comprises, as a firststep, photographically enlarging a conventional gravure screen toprovide an opaque negative photographic print 30 of the desired screenpattern. The particular screen pattern illustrated is known as acrossline screen and comprises two sets of equally spaced parallel blacklines 32 at right angles to each other on a white background. There arethus formed between the black lines 32 of the screen pattern square,sharp-cornered white spaces 34-.

Any other form of gravure screen may be used, but preferably the screenshould be of the same type or pattern as that used in the preparation ofthe cylinder for printing pictorial and display matter, so that theetching procedures for both the type matter and the display matter maybe equalized in timing, acid concentration,

etc. insofar as possible. The screens most frequently used in gravureWork have of the order of 120 to 175 lines per inch, with the width ofthe lines 32 equal to one-half or one-third the width of the inter-linespaces 34. In the particular screen illustrated the ratio of line widthto inter-line space is 1:2.

The screen is enlarged by photographing to such scale as will rendermanual drawing of the type character most convenient. The actual scaleused may be varied according to individual taste and will frequentlydepend upon the intricacy of the strokes and serifs or" the particulartype face, but a lateral enlargement of the order of 40 times has beenfound satisfactory.

As a second step, the artist blacks out as by inking, a portion of ingin shape and size to the strokes which define the typographicalcharacter to be reproduced. Then the artist whites in a marginal area 40around the outline of the strokes of the character, this area suitablybeing of a width of the order of that of the black lines 32 of thescreen pattern. This leaves visible within such White marginal outline40 the pattern of black lines 32 and white spaces 34 of the screen. Asapparent, the white margin 40 has the appearance of merging with those wite spaces 34 of the mate reproduction.

According to one method the negative character outline 38 while thescreen pattern outline 40.

Alternatively, the artist may prepare the positive character shown inFigure 4 directly Without first preparing the negative shown in Figure3. In doing so, he may either use an enlarged positive photographic aprint having groundand White in black out the character defining area38. he may draw up the character including the screen pattern entirelyby hand.

As a further step the character of Figure 4 is then photographed, thistime opaque screen lines 32 but transparent marginal spaces 34'. Thistransparency, as shown in Figure 5, may be cut to form a circular plaque42 for mounting in a matrix generally indicated at 44. The matrix 44will be recognized as of the form described in Patent No. 2,231,899 toH. R. Freund and used in conventional high-speed photocomposingmetchines such as that shown in Patent No. 2,391,021 to E. G.Klingenberg et a1. Alternatively, the matrix may be of the typedisclosed in Patent 6 No. 1,543,527 to R. J. Smothers wherein both thecharacter and the background are opaque, but 0:" contrasting colors; or,the character images, instead of being on circulating matrices, may bemounted upon a rotatable drum, as in machines of the type disclosed inPatent No. 636,062 to Francis H. Richards. In all such machines, thecharacter images are serially exposed, either intive surface and suchsurface is afterward developed to form a positive transparency of thecomposed type matter. A portion of such transparency is shown in Figu "e6; it has a transparent background and screen lines 32, With lettershaving opaque marginal outlines 49 and screen spaces This positivetransparency is then placed against the carbon tissue and the carbontissue is exposed to light through the transparency. No separateexposure of the tissue to a linescreen is necessary, since theindividual characters formed in accordance with the invention alreadycontain the required screen pattern. Where the same carbon tissue usedfor preparing the gravure cylinder to print pictorial matter as well astype matter, the portion of the carbon tissue embodying type matter maybe masked to prevent exposure thereof While that portion of the tissueembodying the pictorial matter is exposed, as it must be, to theline-screen.

The carbon tissue is next applied against the cylinder and developed andthe cylinder then is etched through it. The surface of the cylinder willthen appear as shown in Figure 7, wherein each of the characters of thetype matter etched on the cylinder has within its outline thedepressions 2i) corresponding to the screen spaces 4, and upstandingridges 22 corresponding to the lines 32 of the screen pattern. Aroundthe entire outline of the character there is a channel or gutter 48merging with the depressions 2D ridges 22 to tinuous channel 48 afterthe action of the doctor blade are left filled with ink, which, sreadingevenly from such continuous channel 46 around the outline of eachcharacter, Will form an impression upon the paper having straight, sharpand even outline defining edges 38, such as shown in Figure 8.

An alternative form of character is illustrated in Figure 9. This isformed according to any of the methods described above, but has asinglene screen instead of a cross-line screenthat is, it has only oneset of spaced parallel lines 48, whereby elongated, inter-line spaces 59are formed across the strokes of the characters and merge with themarginal outline 48 formed around the character according to theinvention. The lines 48, as in the previous embodiments, terminate shortof the character defining outline 38, so that the embodiment of Figure 9affords the advantageous results described above. Figure 9 accordinglyillustrates one of the alternative forms of gravure screen which may beutilized in the practice of the present invention.

No matter which of the methods described is employed, only one masterset of typographical and these may be used again and again in thecomposition of type matter.

It will be apparent that the invention. provides commerciallypracticable methods and means for enabling the production of type matterof the required fine quality by the gravure printing processes. However,it should be emphasized that the particular methods and means shown anddescribed are intended as merely illustrative of the invention and in noway restrictive thereof.

I claim:

1. A type character-bearing element for use in the photographicreproduction of type matter by the gravure process, said elementbearing, against an opaque background, a typographical charactertranslucent except for an internal pat tern of spaced, opaque linesextending substantially throughout the entirety oi said character butterminating short of the outline thereof to leave a substantiallycontinuous translucent margin extending around said outline.

A type character-"nearing matrix for use in the photographicreproduction of type matter for printing by the gravure process, saidmatrix having an opening through the body thereof, a plaque mounted insaid opening having an opaque background and bearing a typographicalcharacter translucent except for an internal pattern of spaced, opaquelines extending substantially throughout actor but terminating short ofthe outline thereof to leave a substantially continuous translucentmargin extending around said outline.

3. In a photographic recording machine or" the type wherein typecharacters are serially exposed to a photosensitive surface to form athe entirety of said charphotographic record of composed type matter,

the combination therewith or" a type characterbearing element bearing,in an opaque background, a typographical character translucent exceptfor an lines extending tirety of internal pattern of spaced, opaquesubstantially throughout the ensaid character but terminating shortchine of the type wherein type character-bearing matrices are seriallyand individually exposed to a photosensitive surface to form aphotographic record of composed type matter, the

combination therewith ing matrix of duction of a type character-bean thephotographic reproby the for use in type matter for printing gravureprocess, said matrix having an opening through the body thereof, aplaque mounted in said opening having an opaque background and bearing atypographical character translucent except for an internal pattern ofspaced, opaque lines extending substantially throughout the entirety ofsaid character of the outline thereof to but terminating short leave asubstantially continuous translucent margin extending around saidoutline.

HERMAN R. FBEUND.

References Cited in the file of this patent Number UNITED STATES PATENTS

